Sink



FIG. 1 is a top plan view of the sink of the present invention;

FIG. 2 is a rear elevational view of the sink of FIG. 1;

FIG. 3 is a side elevational view of the sink of FIG. 1; and,

FIG. 4 is a bottom plan view of the sink of FIG. 1. 

The ornamental design for a sink, as shown and described. 